1. Technical Field
The disclosure relates to an ink temperature adjustment device and an ink circulation type inkjet printer which are configured to adjust the temperature of ink to be supplied to an inkjet head configured to form an image by ejecting the ink.
2. Related Art
An ink circulation type inkjet printer has been known which is configured to perform printing by ejecting ink from an inkjet head while circulating the ink. Japanese Unexamined Patent Application Publication No. 2012-153004 describes an ink circulation type inkjet printer including a positive-pressure tank and a negative-pressure tank arranged below an inkjet head, and an air pump configured to send air from the negative-pressure tank into the positive-pressure tank.
When performing printing, this inkjet printer directs air from the negative-pressure tank into the positive-pressure tank with the air pump to thereby apply negative pressure and positive pressure to the negative-pressure tank and the positive-pressure tank, respectively. As a result, ink flows from the positive-pressure tank to the inkjet head. The ink which is not consumed by the ink head is collected into the negative-pressure tank, from which the ink is sent into the positive-pressure tank by an ink pump. The ink circulation is performed in this manner.
Here, for the ink to be circulated, the viscosity of the ink needs to be maintained at certain degrees. For this reason, a temperature adjustment mechanism configured to adjust the temperature of the ink is provided on the ink circulation path. This temperature adjustment mechanism, for example, includes a heat sink and a heater provided on the ink path, and heats or cools the circulated ink passing through the heat sink and heater to maintain the ink at proper temperatures.